Essential Fly Fishing Knots Every Angler Should Know

Fly fishing asks more of knots than most fishing does. Between the reel and the fly there are four separate connections, and every one of them joins materials of different diameter and stiffness. Any of them can fail. Most fail quietly, at the worst moment, on the best fish of the day.

Eight knots cover the whole system. Learn them in the order the line runs.

The system, from reel to fly

Backing. Fly line. Leader. Tippet. Fly. Five components, and a knot at every join.

Connection	Knot	Why that one
Backing to reel spool	Arbor knot	Tied once per reel, then forgotten
Backing to fly line	Albright knot	Slim enough to pass through the guides
Fly line to leader	Nail knot, or loop to loop	Nail knot is slimmer, loops change faster
Loop in a leader butt	Perfection loop	Sits straight instead of cocked to one side
Leader section to leader section	Blood knot	Smooth taper when diameters are close
Leader to tippet	Double surgeon's knot	Fast, and forgiving of mismatched diameters
Tippet to fly	Improved clinch knot	The everyday knot for trout flies
Tippet to fly, streamers	Non-slip loop knot	Leaves the fly free to move

The habit that matters more than which knot you pick

Wet the knot before you draw it tight. Pulling a dry knot closed generates enough friction heat to weaken monofilament and fluorocarbon before the fly ever touches water. Saliva or river water, then seat it slowly.

Two more that cost nothing. Seat every knot with a steady pull and look at it before you fish it. Trim the tag close but not flush, because a tag cut hard against the knot can pull back through under load.

1. Arbor knot

Joins: backing to the reel spool.

1. Pass the backing around the spool arbor.
2. Tie an overhand knot around the standing line with the tag end.
3. Tie a second overhand knot in the tag end itself, an inch past the first.
4. Wet it, then pull the standing line. The first knot slides down and jams against the second, which acts as a stopper.

It only has to hold until the arbor grips. If a fish ever reaches your arbor knot, the knot is not your biggest problem. How much backing the reel takes is a separate question, and the fly reel backing calculator answers it for your reel and line weight.

2. Albright knot

Joins: backing to fly line.

1. Double back the last two inches of fly line to make a loop, and pinch it.
2. Pass the backing through that loop, leaving a long tag.
3. Wrap the backing tag around both strands of the fly line loop, working back toward the loop's closed end, ten to twelve tight turns.
4. Feed the tag back out through the loop, entering the same side it went in.
5. Wet it. Pull on both standing ends slowly so the wraps slide and tighten against the loop rather than bunching.

The wraps have to stay neat. A ragged Albright is bulky, catches in the guides, and is the reason people quietly switch to loops.

Some fly lines ship with welded loops at both ends. If yours has one at the back, tie a perfection loop in the backing and connect the two loop to loop. Skip this knot entirely.

3. Nail knot

Joins: fly line to leader butt.

The name comes from the nail once used to hold the wraps open while you tied it. A short piece of stiff tubing, or a nail knot tool, does the same job and is easier.

1. Lay the fly line, the leader butt and the tube side by side, with the leader tag pointing back along the fly line.
2. Wrap the leader tag five or six turns around all three, working toward the end of the fly line, keeping the wraps tight and touching.
3. Feed the tag back through the tube, then slide the tube out.
4. Wet it. Pull the two tag ends to snug the wraps, then pull the standing ends to seat.
5. Trim both tags close.

The mistake is seating it before the wraps are neat. Once the coils cross each other they will never bed down properly, and the knot slips under a hard pull.

4. Perfection loop

Joins: nothing on its own. It puts a loop in the end of a leader butt so you can connect loop to loop.

Its advantage over other loop knots is that the finished loop sits in line with the standing part rather than cocked off to one side. A crooked loop acts as a hinge and kills the turnover you paid for when you bought a tapered leader.

1. Make a loop with the tag end passing behind the standing line.
2. Bring the tag around again to form a second, smaller loop in front of the first.
3. Bring the tag end back and lay it between the two loops.
4. Reach through the first loop, grab the second loop, and pull it through.
5. Wet it, then pull the loop and the standing line apart to seat. Trim the tag.

5. The loop to loop connection

Not a knot. A connection, and one people get wrong often enough that it deserves its own heading.

Pass the leader loop through the fly line loop. Then pass the whole far end of the leader back through its own loop. Pull them together and the two loops form a neat square.

If instead you pass the fly line through the leader loop and pull, you get a girth hitch. It looks close enough. It is not. A girth hitch cinches down on the other loop at a right angle, creates a hinge, and cuts into the line under load.

6. Blood knot

Joins: two lengths of leader material of similar diameter.

1. Overlap the two ends by six inches or so.
2. Wrap one tag five turns around the other line, then bring it back and pass it through the gap where the two lines cross.
3. Wrap the second tag five turns around the first line, in the opposite direction, and pass it back through the same gap from the other side.
4. Wet it and pull both standing ends steadily. The wraps roll together into a barrel.

It gives the smoothest, slimmest join of any leader knot, which is why it is the one used to build tapered leaders from scratch. It only works when the two diameters are close, within about two X sizes. Past that, the thin side pulls through. Use a surgeon's knot instead.

If you tie your own leaders, the leader formula builder gives you the section lengths and diameters to work from.

7. Surgeon's knot

Joins: leader to tippet.

Double and triple surgeon's are the same knot with a different number of passes. Two passes is a double surgeon's, three is a triple. More passes means more security and more bulk.

1. Lay the leader end and the tippet end alongside each other, overlapping by six inches, pointing in opposite directions.
2. Treating the two as one, form a simple loop.
3. Pass the tippet tag and the whole leader end through that loop twice for a double, three times for a triple.
4. Wet it. Pull all four ends at once, evenly, so the knot draws down square rather than skewed.

It is faster than a blood knot, easier with cold hands, and it tolerates a much bigger diameter mismatch. The trade is a slightly bulkier knot that sits at an angle rather than in line. On a trout leader that costs you nothing worth measuring.

8. Improved clinch knot

Joins: tippet to fly. This is the one you will tie more than all the others combined.

1. Pass the tippet through the hook eye, leaving six inches of tag.
2. Wrap the tag five turns around the standing line.
3. Bring the tag back and pass it through the small loop right against the hook eye.
4. Then pass it through the large loop you just created. That second pass is the improved part, and skipping it is the most common way this knot fails.
5. Wet it and pull the standing line to seat the coils neatly against the eye. Trim.

Five turns suits typical trout tippet from 3X to 6X. On heavier material, three or four turns is enough, and more just makes it bulky and hard to seat.

9. Non-slip loop knot

Joins: tippet to fly, when you want the fly to move.

A clinch knot pulls tight against the hook eye and holds the fly rigid. On a weighted streamer or a big articulated fly that stiffness kills the jigging action you tied the fly for. A loop knot leaves the fly swinging free.

1. Tie a loose overhand knot in the tippet, six inches from the end.
2. Pass the tag through the hook eye, then back through the overhand knot, entering the same side it exited.
3. Wrap the tag around the standing line. Four to seven turns depending on diameter, more turns on lighter tippet.
4. Bring the tag back through the overhand knot once more, same side as before.
5. Wet it. Pull the tag to snug the wraps, then the standing line to seat the whole thing. The overhand knot closes and locks the loop at whatever size you left it.

Leave the loop small, a quarter inch or less. A big loop does not add action, it just gives the fly somewhere to tangle.

If you only learn two

Learn the double surgeon's and the improved clinch.

Those two let you fish a store-bought tapered leader, add tippet as the leader shortens, and change flies all day. The rest of the list matters the first time you spool a reel and then rarely again.

Why knots fail, and how to read the evidence

The broken end tells you what happened. Look at it before you retie.

• A curly pigtail on the tag end. The knot slipped rather than broke. Too few turns, or it was never fully seated.
• A clean break right at the knot. Usually seated dry, or seated too fast. Heat and friction did the damage before the fish did.
• A break above the knot, in the tippet itself. Abrasion. Run the last few feet of tippet between your fingers after any fish, any rock, and any tree. If it feels rough, cut it back.
• Repeated failures on fluorocarbon. Fluorocarbon is stiffer and less forgiving than nylon. Wet it more, seat it slower, and add a turn.

Tools that take the guesswork out

Knots are only half of a rig. The other half is choosing the right diameter to tie in the first place.

• Fly fishing leader calculator for total leader length and taper by situation.
• Tippet size calculator for diameter and breaking strength by X rating.
• Fly size to tippet matcher for the balanced tippet range for any hook size.
• Fly line weight chart for matching line to rod.
• All fly fishing tools and charts.

Questions anglers ask about fly fishing knots

What is the strongest knot for tippet to fly?

The honest answer is that a well tied knot beats a theoretically stronger one tied badly. In tests the non-slip loop knot retains more of the line's rated strength than a clinch on heavier tippet. At trout diameters, a properly seated improved clinch is not the weak point in your rig. Your tippet choice is.

Do I still need a nail knot if my fly line has a welded loop?

No. Tie a perfection loop in the leader butt and connect them loop to loop. It is faster, and it lets you change leaders on the water in under a minute.

How many turns should an improved clinch knot have?

Five for 3X through 6X. Three or four on heavier material. Fewer turns on thick line, because the coils need room to seat against each other.

Why does my leader keep breaking right at the fly?

Three usual causes. The knot was seated dry, the tippet was abraded before it broke, or the tippet is too heavy for the fly and the knot is not seating properly on a small hook eye. The fly size to tippet matcher rules out the third.

Blood knot or surgeon's knot?

Surgeon's for speed, for cold hands, and whenever the two diameters differ by more than about two X sizes. Blood knot when you want the slimmest, straightest join and the diameters are close, which mostly means when you are building a leader at the vise rather than fixing one on the bank.

Does it matter which knot I use for dry flies?

The improved clinch is standard and it works. Some anglers prefer a loop knot on larger dries and hoppers so the fly sits more naturally and is not pulled down at the nose. On small dries, size 18 and under, the clinch is easier to tie and easier to seat on a tiny eye.